1. Field of the Invention
This invention relates in general to hydraulic couplings, and specifically to hydraulic couplings used in undersea drilling and production applications. More particularly, this invention involves hydraulic coupling members having radial or angled flow ports.
2. Description of Related Art
Subsea hydraulic couplings are old in the art. The couplings generally consist of a male member and a female member with sealed fluid passageways connecting therebetween. The female member generally is a cylindrical body with a relatively large diameter longitudinal bore at one end and a relatively small diameter longitudinal bore at the other. The small bore facilitates connections to hydraulic lines, while the large bore seals and slidingly engages the male member of the coupling. The male member includes a cylindrical portion at one end having an outer diameter approximately equal to the diameter of the large bore of the female member of the coupling. The male member also includes a connection at its other end to facilitate connection to hydraulic lines. When the cylindrical portion of the male member is inserted into the large bore of the female member, according to various embodiments of the device, fluid flow is established between the male and female members. Couplings of this type are shown in patents owned by National Coupling Company, Inc. of Stafford, Tex.
In undersea drilling and production applications, the male member of the coupling may be connected to a manifold plate or other securement at a subsea location at the inside or outside of a well bore. In many cases, the male members are positioned so that the end or leading face of each member points vertically up from the sea floor. The female members, which also may be secured to a manifold plate, are moved into position over the male members and then lowered onto the male members by a diver or subsea vehicle. When the female members are positioned on the male members, hydraulic fluid typically is from the female member to the male member of the coupling. In some cases, only the female member of the coupling has a poppet valve.
The poppet valve typically includes a conical valve face which seats, in the closed position, against a valve seat in the coupling member. The poppet valve opens to allow fluid flow, and closes against the valve seat within the bore to arrest the flow. Generally, the poppet valve is spring-biased to the closed position. The valve may include a valve actuator which may be a nose or stem extending from the apex of the valve face along the longitudinal axis of the poppet valve.
Frequently, well bores in which couplings are positioned are full of debris. The male member, which may remain subsea when the coupling is disconnected, is subject to debris accumulating in flow passages. The flow passages in the male member may be directly across the gap between the valve face and the valve seat, as shown in U.S. Pat. No. 4,694,859. Or, as shown in U.S. Pat. Nos. 4,654,780, 5,099,882 and 4,832,080 to Robert E. Smith, III, hydraulic flow may be radially between the members. Either configuration may be subject to ingress of debris. The debris may contaminate the hydraulic fluid or cause wear to the seals and sealing surfaces in hydraulic couplings and hydraulic systems.
U.S. Pat. No. 5,692,538 to Robert E. Smith, III describes an undersea hydraulic coupling member having flow ports that are angled to help prevent ingress of debris into the hydraulic lines when the coupling members are disconnected. The coupling of U.S. Pat. No. 5,692,538 includes a cylindrical passageway where the valve stem or actuator is positioned. Although the coupling of U.S. Pat. No. 5,692,538 can effectively prevent ingress of debris, it is desirable to increase the flow rate of hydraulic fluid through the coupling. Additionally, the poppet valve shown in U.S. Pat. No. 5,692,538 is opened in response to fluid pressure, rather than engagement of a valve actuator with the opposing valve actuator of the female member.
Accordingly, it is desirable to provide an undersea hydraulic coupling with radial or angled flow ports to help prevent ingress of debris, but that will have a higher flow rate through the coupling member and a valve actuator configured to open the valve when mutually engaged with the female coupling member valve actuator.
The present invention resides in an undersea hydraulic coupling member having an external port guard around the radial or angled flow passages in the probe. When the poppet valve of the coupling member is in the closed position, the external port guard is biased to a position in which it covers the flow ports.